// OPCION 1

document.getElementById("double-tap").addEventListener("touchstart", tapHandler);

var tapedTwice = false;

function tapHandler(event) {
    if(!tapedTwice) {
        tapedTwice = true;
        setTimeout( function() { tapedTwice = false; }, 300 );
        return false;
    }
    event.preventDefault();
    //action on double tap goes below
    alert('You tapped me Twice !!!');
 }
 
 // OPCION 2
 
var tapped=false
$("#mini-cart .dropdown-toggle").on("touchstart",function(e){
    if(!tapped){ //if tap is not set, set up single tap
      tapped=setTimeout(function(){
          tapped=null
          //insert things you want to do when single tapped
      },300);   //wait 300ms then run single click code
    } else {    //tapped within 300ms of last tap. double tap
      clearTimeout(tapped); //stop single tap callback
      tapped=null
      //insert things you want to do when double tapped
    }
    e.preventDefault()
});